Cytisus aeolicus Guss. ex Lindl. in vitro cultures and genistin production

Cytisus aeolicus Guss. ex Lindl. (Fabaceae family, subfamily Faboideae) is an endangered endemic species of the Aeolian Islands, Sicily. In vitro multiplication of C. aeolicus shoots was described in this work and cell cultures were established from cotyledons and hypocotyls to investigate their potential production of isoflavones. Aseptically germinated seeds, cultivated on LS modified basal medium, gave the initial explants used both to induce axillary propagation and callus cultures. The LS (Linsmaier and Skoog) basal medium, supplemented with 0.1 mg L-1 of 6-benzylaminopurine were used to induce axillary propagation. The callus induction was performed using the basal medium added with 5 mg L-1 2,4-dichlorophenoxy acetic acid and 5 mg L-1 kinetin (control medium). Basal medium was also added with 2000 mg L-1 casein hydrolysate (CH) or 900 mg L-1 myo-inositol (MI). C. aeolicus callus cultures on CH and MI media produced an unique compound, the isoflavone genistein 7-O-ß-D-glucopyranoside (genistin), which has not previously been isolated from wild plants. Callus cultures grown on the medium containing myo-inositol produced the greatest amount of genistin. C. aeolicus tissue culture procedures could provide suitable plant material both for germplasm preservation (by micropropagation) and for biotechnological selective isoflavone production (by callus culture).